X-ray tube.



J. D. GIBSON X-RAY TUBE.

APPLICATION FILED JULY 31,1914.

Patented A101. 25, 1916.

IN VEN TOR.

JEFFERSON JD. GIBSON, OI DENVER, COLODQ.

X-RAY TUBE.

M I Specification of Letters Patent.

maoooa.

Application filed July 31,

To all whom it may concern:

Be it known that I, JEFFERSON D. GIBSON, a citizen of the United States, residing in the city and county of Denver and State of Colorado, have invented certain new and useful Improvements in X-Ray Tubes; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to improvements in X-ray tubes, and the primary objects of the invention are the positioning of the primary or main anode or anticathode and tube; making said anode hollow; pos1t1ve means for cooling the anode and anode tube; and protecting means shielding the anode and anode tube from the rays emitted from the secondary anode.

It is understood that the converging rays from the cathode, impinging upon the reflecting surface of the anode, causes the latter to become so highly superheated that the intensity of the diminished or the use of the tube temporarily discontinued. I am aware that this eX- cessive heating of the anode has been partially overcome, but not-wholly remedied, by various means, in some of which the anode is even made hollow to receive and contain water, but the heat is so intense that in such cases the cooling water is so rapidly generated into steam that the cooling operation quickly becomes ineffective, and there is a great likelihood of the reflecting wall of the anode being burnt through at the focal point of the converging rays from the cathode. It mayalso be stated that in the employment of such cooling means, as just described, the primary anode and tube' are arranged at an obtuse angle to the-cathode tube the secondary anode is arranged in longitudinal alinement with the cathode, and in no case, that I am aware of, has the primary anode and tube and the joinder therebetween been shielded or protected from the rays emitted from the secondary anode, the

\ impingement of which rays cause the primary anode and associated parts to rapidly deteriorate.

It is the aim of the present invention, therefore, to overcome the objectionable features stated, and to produce an X-ray tube that is not only durable and eficient in acelectrlc current must beon the main bulb, and

is open at its inner end 8, the

Patented a as, rate.

1914. Serial No. 854,324.

tion, but which is also substantially as simple in construction as those heretofore in use, and one whose usefulness is indefinitely prolonged.

With these and other objects in view, the invention consists of the novel features of construction and in the arrangement and combination of parts, as will be more fully described in the following specification and more succinctly pointed out in the appended claims.

In the accomplishment of mvention generically consists of a main anode tube provided at its inner end with a hollow anode, the said tube being arranged in longitudinal alinement with the cathode; a second tube or shield for the main tube and anode; and novel cooling means, wherethese ends, the

by an entering cooling fluid is caused to impinge directly against the lnner surface of the reflecting wall of the anode, and at a position directly opposite the focal point of the converging rays from the cathode, or at the point of greatest heat intensity. It will be understood, however, that changes might be made in the manufactural construction and arrangement of parts without departing from the spirit of the invention or without sacrificing or vitiating any of the vital principles thereof.

While the invention is not limited, therefore, to the exact details shown and described, still for the purpose ofa full and complete disclosure referenceis had to the accompanying drawings, in which the single figure is a view partly in elevation and partly in longitudinal section, the section being taken through'that portion of the X- ray tube embodying my invention.

1 designates the bulb or body portion of an X-ray tube of any suitable form. 2 is the cathode, 3 an anode, and 4 is a vacuum regulating bulb, all of which are common to other forms of X-ray tubes, and in themselves form no part of the present invention.

5 is a hollow tubular extension on the bulb 1, within which is mounted a glass tubular sheath or outer tube 6, the tubular extension. and the tubular sheath being fused together at 7, providing an air tight seal to maintain a vacuum within the bulb. This tubular sheath 6 extends inwardly and inner end being cut off on a bevel as shown. The outer tube also extends outwardly and is provided with a nipple 9, closed at its outer end, and hollow interiorly forming a chamber 10, and also providing for a terminal 11 for the lead-in wire, 12 designating a connecting wire between the terminal 11 and the terminal of the anode 3. Y

W'ithin the outer tubular shield -7 is mounted the anticathode tube 13 fused to the tube 7 at 11 to form an air tight seal.

On the inner end of this tube 13 is mounted the anticathode 15, which as shown'consists of a hollow member made of platinum,

tungsten, or any other suitable metal,pthe

outer end of which is closed by a beveled wall 16, opposed to the cathode and comprising a reflecting surface for intercepting and projecting the rays from the cathode. The inner ends of the hollow anticathode and the anticathode tube may be o1ned to gether in any suitable way, a convenient means being shown at l7, where the'inner end of the hollow metallic anticathode is provided with an annular depression withinwhich is depressed the end of the glass anticathode tube 13, after heating, forming a fused joint therebetween. Extending longitudinally within the anticathode tube 13 is an inner glass tube 18 of small diameter,

sealed to the outer end of the tube 6, as at 19, and communicating with the chamber 10.-

The inner end of this tube 18 is cut oif on a bevel parallel to the beveled wall 16, and

this open end 20 isslightly spaced from said wall 16, and is positioned centrally thereof or opposite the focal point of the converging rays from the cathode.

21 designates the lead-in wire for the I anticathode from the terminal 11, which wire extends through the inner tube 18 and may be provided at its inner end with a metallic'piece 22, which is fused or soldered to the inner face of the wall 16. The inner tube 18 and the anticathode tube 13 form may be located in any position with regard to the outlet chamber. 7

2'8 simply designates a rubber tube leading to the source of fluid supply.

In describing the several tubes and their positions of 'joinder, I have simply referred to the various parts as a completed whole. In the actual manufacture ofthe parts the same may be separately blown and afterward assembled and joined together in any suitable manner well known inthe art-of glass blowing.

From the foregoing complete description it is believed that the operation Will be sufiiciently clear, but it may be stated that any coo-ling fluid, gaseous or liquid, such as air or water is introduced through the nipple 26 under pressure; passes into the chamber 10; thence through the inner tube 18, enveloping the lead-in wire; and is caused to impinge directly against the inner face of the reflecting wall 16 at the position of the greatest heat intensity; and after circulating around within the hollow anticathode'is caused to travel back through the anticathode tube 13, emptying into the chamber 25 and exhausting through the outlet nipple 27, the whole arrangement permitting of a positive, forced, and continuous circulation of the cooling medium through the hollow antlcathode and anticathode tube, increasing in a. marked and lasting degree the efiiciency and life of the tube. Also the tubular sheath or shield 6 intercepts the positive rays from the secondary anode, preventing them from being projected against the main anode or anticathode and tube as and for the purpose hereinbefore stated.

It is obvious that the outlet nipple maybe located at any position. or angle, and while I prefer the use of cooling air, the position of-the outlet nipple. as shown, is peculiarly adapted for use with acooling liquid, as in this position the tube 13 must be maintained full before it.will overflow, which would not be the case if the outlet nipple was arranged on the opposite side.

aving thus described the in\'ention,\vl1at 1 I claim is 1. In an X-ray tube, the combination of a-ma-in bulb, a cathode in said bulb,'an anode therein. an anti-cathode tube inserted through said bulb, an annular. internal bead on the inner end of said tube, an anti-cathode member provided with an annular depression for receiving said bead, an inner tube within'said anti-cathode tube and in communication with the interior of said member, and means'for circulating a cooling medium through said tubes, substantially as described. a

2. In an X-ray tube, the combination of a main bulb, a cathode, an anode, a tubular extension formed on said bulb opposite the cathode, a tubular shield fitted through said extension, an anti-cathode tube supported within said shield, an anti-cathode member connected to said tube and extending beyond the inner end of said shield, an inner tube within said anti-cathode tube and member, an electrode in said inner tube, chambers formed at the outer ends of said tubes, and

connections for placing said chambers in communication with a circulating system for delivering a cooling medium to and through said tubes, substantially as described.

3. In an X ray tube, the combination of ma aaa a main bulb, a cathode supported in said bulb, an anode also supported in said bulb, a tubular extension formed on said bulb opposite the cathode, an anti-cathode tube inserted through said extension, an anti-cathode member supported on the inner end of said tube, an inner tube mounted centrally within said anti-cathode tube and member and terminating short of the operating face of the latter, an electrode in said inner tube, an enlarged piece on the end of said electrode in contact with the operative face of said member, an electrical connection between said electrode and anode, chambers formed at the outer ends of said inner and anti-cathode tubes, and connections including said chambers in a circulating system for delivering a cooling medium through said tubes and anti-cathode member, substantially as described.

4. In an X-ray apparatus, the combination of a bulb, a cathode in said bulb, an anode in said bulb, a tubular extension formed on said bulb axially of said cathode, a tubular shield mounted in said extension and provided with an inclined inner end terminating substantially at the center of the bulb, an anti-cathode tube located within said shield and connected thereto at its outer end, an annular bead formed on the inner end of said anti-cathode tube, an anticathode member provided with an annular depression for receiving said bead and formed with an inclined outer end projecting beyond the end of said shield, a chamber formed at the outer end of said anticathode tube, an inner tube located within said anti-cathode tube and provided with an inner beveled end located adjacent the end of said anti-cathode. member, an electrode in said inner tube, a chamber formed at the outer end of said inner tube, a connection for delivering a cooling fluid to said lastnamed chamber, and means connected to said first-named chamber for exhausting the fluid circulated through said inner and anticathode tubes, substantially as described.

5. In an X-ray apparatus, the combination of a main bulb, a cathode, an anti-cathode comprising a hollow member provided with an angularly-disposed face with reference to said cathode, an annular depression formed at the rear end of said anti-cathode member, an anti-cathode tube connected to support said member and having its end contracted to fit the depression therein, a chamber formed at the outer end of said anti-cathode tube, a tubular shield fitted through said bulb and arranged in spaced relation enveloping said anti-cathode tube and member and formed with a beveled end corresponding and terminating short of the angular end of said member, an inner tube arranged substantially centrally within said anti-cathode tube and provided with an inclined end positioned in close proximity to the beveled end of said member, a second chamber located at the outer end of said inner tube, an electrode arranged in contact with the inclined end of said member, an anode, a connection between said anode and electrode, and means connecting said chambers in a circulating system for delivering a cooling medium to the anti-cathode, substantially as described.

In testimony whereof, I afiix my signature, in presence of two witnesses.

JEFFERSON D. GIBSON.

Witnesses:

J. S. GIUs'rA, LILLIAN F. COOPER. 

